1. Field of the Invention
The present invention relates to a method for calibrating a measuring device in a mobile terminal, and to a mobile terminal having a measuring device that is calibratable in the operating mode.
2. Description of the Related Art
A method is known for deducing the ambient temperature of the mobile terminal on the basis of two temperature sensors that are positioned at different locations in a mobile terminal. Such a method is known, for example, from the published European patent application document EP 1 301 014 A1.It aims to facilitate the measurement of ambient temperature, even when the self-generated heat of the mobile terminal prevents a direct measurement of the ambient temperature. Namely, during operation, individual components of the mobile terminal typically generate heat that is registered by the temperature sensor. Since the temperature sensor cannot be arbitrarily far from the heat source, and in order to disregard the influence of the heat source, it is common practice to ascertain the temperature gradient between two temperature sensors and to extrapolate the ambient temperature, a first temperature sensor typically being configured inside of the mobile terminal, while a second temperature sensor is positioned at an exposed location on the mobile terminal. To improve the accuracy of the measuring device using the two temperature sensors, the integral temperature sensors are calibrated during the production process of the mobile terminal. In order for the calibration process to be carried out within a time frame that is justifiable for the production process of the mobile terminal, the calibration is restricted to two temperatures, without taking the thermal response times into consideration.